Tank washer

ABSTRACT

An automatically operable tank washer. A power head drives a screw through a fixed nut to rotate a nozzle assembly while moving the nozzle assembly lineally. A linkage causes the nozzle on the nozzle assembly to swivel during lineal movement of the nozzle assembly. The power head includes a piston-operated reversible rotary motor that is controlled by the supply of air to a four-way automatic reversing valve with spring-loaded mechanical switches. An automatic throttle valve to vary the speed of the motor in response to the lineal position of the screw. An automatically operable cam valve to vary the speed of the motor during each 360* cycle of rotation of the screw. Means for interchanging screws to vary the pitch of the screw. Means for interchanging cams to select the patterm of rotational speed variation.

United States Patent Guignon et al. [4 1 Oct. 10, 1972 TANK WASHER Primary Examiner-Edward C. Allen [72] Inventors; John Guignon; Helen Attorney-Kingsland, Rogers, Ezell, Eilers & Robbins Guignon, both of 12 Clipper Road, St. Louis, Mo.; John E. Guignon, Jr., 5653 Sanger, Apt. 22, Alexandria, Va.

[57] ABSTRACT An automatically operable tank washer. A power head drives a screw through a fixed nut to rotate a nozzle assembly while moving the nozzle assembly lineally. A linkage causes the nozzle on the nozzle assembly to swivel during lineal movement of the nozzle assembly. The power head includes a piston-operated reversible rotary motor that is controlled by the supply of air to a four-way automatic reversing valve with spring-loaded mechanical switches. An automatic throttle valve to vary the speed of the motor in response to the lineal position of the screw. An automatically operable cam valve to vary the speed of the motor during each 360 cycle of rotation of the screw. Means for interchanging screws to vary the pitch of the screw. Means for interchanging cams to select the patten'n of rotational speed variation.

18 Claims, 23 Drawing Figures PATENTED 0B7 10 I972 3.6 96, 825

sum 1 or 3 SUPPLY NEEDLE VALVE vmg PRESSURE lm/EN-roRs: JOHN E. ulewolv, HELEN 6.6U/GNON, JOHN E. Gu/GNONJQ.

TANK WASHER BRIEF DESCRIPTION OF THE INVENTION This invention provides a fast-operating automatic tank washer. The tank washer may be used for cleaning any kind of tank and it is especially suitable for cleaning chemical reactor tanks where speed of cleaning is an important economic consideration, freedom from personal contact with the contaminants in the tank is a health consideration, and freedom from any possibility of electrical arcing because of the possible presence of explosive gases is a safety consideration.

In cleaning such chemical reactor tanks, the tank washer is first operated through its cycle to spray clear water over the interior surface of the tank to remove up to 90 percent of the sludge from the walls of the tank. After the wash water is drained from the tank, the tank washer is again operated through its cycle to spray solvent against the interior surfaces of the tank to remove all the remaining sludge and foreign matter from the inner surface walls of the tank. Then the solvent containing foreign matter in the tank is circulated again through the tank washer, but this time the solvent is mixed with water so that, when the sprayed mixture of solvent and water is collected within the tank, the solvent and water can be removed and delivered to a suitable conventional press for separation and recovery of the solvent. Finally, the tank washer is again operated through its cycle to spray clear rinse water against the interior surfaces of the tank to remove any remaining solvent and the'clear rinse water is drained from the now clean tank.

In brief, the tank washer has a power head that comprises a cylindrical housing. A reversible pistonoperated rotary motor is slidably mounted within the housing. A threaded rod or screw is connected to the outlet shaft of the motor, and a pipe is connected to the lower end of the threaded rod. The threaded rod is threaded through a fixed nut, so that, as the rod is rotated by the motor, it is driven upwardly or downwardly as it turns through the fixed nut. The pipe slides through sealed bearings in a liquid outer jacket, and openings through the side wall of the pipe permit liquid admitted to the outer jacket to flow into the pipe. A nozzle assembly is connected to the lower end of the pipe. The nozzle assembly comprises a nozzle manifold that is rotatably mounted on a horizontal axis and has a plurality of nozzles projecting from it. A lever assembly is connected between the nozzles and a collar on the liquid outer jacket, so that, as the pipe moves linearly downwardly or upwardly, the lever assembly forces the nozzles to oscillate. There are spring-loaded closure valves for automatically blocking the nozzle outlet orifices when the nozzles are directed in predetermined directions.

The nozzles incorporate a disc insert that has a plurality of passages of circular cross section that act as stream straighteners to remove turbulence of the liquid prior to its flowing through the nozzle outlets.

An automatic throttle valve is provided for varying the supply of air to the air motor in response to the lineal position of the rod and pipe. Thus, lineal speed of movement of the nozzle assembly is automatically varied by the automatic throttling valve. Also, the air motor is automatically reversed by an automatically operating four-way reversing valve. This four-way reversing valve has mechanical switches that are actuated by actuator plates which move with movements of the threaded rod. Electrical switches that might produce arcing are eliminated.

Variations in speed of the motor during each 360 cycle of rotation are provided by a cam valve. The cam valve operates with a cam follower that follows a cam surface. The cam surface is on an interchangeable cam to enable selection of an appropriate cam surface configuration for different tank-cleaning projects. The variable speed produced by the cam operated valve is superposed on the variable lineal speed produced by the automatic throttling valve.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of the tank washer.

FIG. 2 is an enlarged view in longitudinal medial section through the upper portion of the tank washer.

FIG. 3 is a fragmentary view in longitudinal medial section through the lower portion of the tank washer. FIGS. 2 and 3 illustrate the screw and pipe in their uppermost positions.

FIG. 4 is a view in section taken along the line 4-4 of FIG. 2.

FIG. 5 is a further enlarged fragmentary view in longitudinal medial section showing the upper bearing assembly.

FIG. 6 is an enlarged view in longitudinal medial section showing the lower bearing assembly.

FIG. 7 is a fragmentary elevation view of the lower portion of the tank washer as viewed from the right of FIG. 1.

FIG. 8 is a view in section taken along the line 8-8 of FIG. 7.

FIG. 9 is a view in section taken along the line 9-9 of FIG. 8.

FIG. 10 is a side elevation view of the snap action four-way valve actuated to one condition, as viewed in FIG. 2 if the throttle valve were removed.

FIG. 11 is a side elevation view of the snap action four-way valve actuated to another condition.

FIG. 12 is a front elevation view of an alternative nozzle manifold with the nozzles open.

FIG. 13 is a side elevation view of the nozzle manifold in the open nozzle condition.

FIG. 14 is a front elevation view of the nozzle manifold with the nozzles closed.

FIG. 15 is a side elevation view of the nozzle manifold in the closed-nozzle condition.

FIG. 16 is a view in section taken along the line 16- 16 of FIG. 13.

FIG. 17 is a view in section taken along the line 17-- 17 of FIG. 12.

FIG.=18 is a view in section taken along the line 18-- 18 of FIG. 12.

FIG. 19 is a view in section taken along the line 19- 19 of FIG. 12.

FIG. 20 is a view in section taken along the line 20- 20 of FIG. 14.

FIG. 21 is a view in section taken along the line 21- 21 of FIG. 14.

FIG. 22 is a viewin section taken along the line 22- 22 of FIG. 14.

FIG. 23 is a fragmentary elevation view in section showing a modified form of nozzle.

DETAILED DESCRIPTION OF THE INVENTION The tank washer 20 has a housing 21 that is in the form of a cylinder having an upper end 22 and a lower end 23. A reversible, piston-operated, rotary air motor 24 is slidably mounted in the upper end of the cylindrical housing 21. A plate 25 is fastened to the lower side of the motor 24 by a plurality of bolts 26. A central opening 27 in the plate 25 accommodates the rotatable output shaft 28 of the motor 24.

A rod 31 extends below the motor output shaft 28. The rod 31 is releasibly connected to the output shaft 28 by a collar 32 that has one bolt 33 threaded against the motor output shaft 28 and another bolt 34 threaded through the rod 31. A large cam 35 is threaded onto the rod 31 and is locked in place by a key 36. The cam 35- has an eccentriccam surface 37 as shown in FIG. 4 and has a function that will be described in more detail hereinafter. The cam 35 is removable so that other cams having other cam surface configurations may be substituted.

Another threaded rod 38 is connected to the rod 31 by a collar 39 that has one bolt 40 extending through the rod3l and another bolt 41 extending through the rod 38. The rod 38 is threaded through a stationary nut 42'that is removably fixed in place within a split plate 43 by a key 44. The split plate 43 is mountedwithin the housing 21 by a plurality of bolts 45. The lower end of the rod 38 is connected to the upper end of a pipe 46 that has a block 47 threaded into its upper end to act as a water-tight seal. A bolt 48 is threaded through the upper end of the pipe 46, the block 47 and the rod 38 to connect the rod 38 to the pipe 46.

A cylindrical liquid outer jacket 50 is connected below thehousing 21. The outer jacket 50 has an upper end 51 and a lower end 52. A plurality of sleeves 54 are positioned between" the housing 21 and the outer jacket 50 with a bolt 55 extending through each sleeve. A nut 56 is threaded onto the end of each bolt 55. A liquid inlet pipe 57 leads to the outer jacket 50. The liquid inlet pipe 57 has an annular flange 58 welded to its outer end to enable connection to a supply pipe that delivers water with or without various cleaning compounds.

The pipe 46 extends through the outer jacket 50 and is slidable between two bearing members 60 and 61. As shown in FIG. 5, the. upper bearing member comprises two rings 62 and 63 positioned between an annular shoulder 64 projecting inwardly from the inner surface of the outer jacket 50 and the nut 56. The rings 62 and 63 are vertically spaced from one another, and a tube 65 is connected through the side wall of the outer jacket 50 and leads from a source of compressed air (not shown) to deliver compressed air to the space between the bearing rings 62 and 63 at a pressure of approximately psi above the wash or tank pressure. A pair of O-rings 66and 67 in the bearing ring 62 provide seals against the outer jacket 50 and the pipe 46 respectively. A pair of O-rings 68 and 69 in the bearing ring 63 .provide seals against the pipe 46 and the outer jacket 50 respectively. The high pressure air supplied through the tube 65 is further assurance that no liquid will flow from within the outer jacket 50 past the bearing member 60.

As shown in FIG. '6, the lower bearing member 61 comprises a bearing ring 72 that is tightly fitted within the lower end of the outer jacket 50 and is positioned against an annular shoulder 73. A plurality of bolts 74 extends through a bearing collar 75 which will be described more fully hereinafter. Nuts 76 on the inner ends of the bolts 74. bear against the lower side of the bearing ring 72. A pair of O-rings 77 and 78 in the bearing ring 72 provide liquid-tight seals against the pipe 46 and the water jacket 50 respectively.

The pipe 46 has openings 80 in its side wall to permit liquid flowing from the liquid inlet pipe 57 to flow into the pipe 46. The lower 'end of thepipe 46 is bolted to the header 81 that has a horizontally oriented cylindrical sleeve 82, both of which constitute the housing parts of a nozzle assembly 83.

A'cylindrical nozzle manifold 84 is rotatable within the sleeve 82. End caps 85 are fastened to the outer ends of the nozzle manifold 84 by a plurality of bolts 86. The nozzle manifold 84 has openings 87 through its side wall to permit liquid communication from the pipe 46 to the nozzle manifold 84 regardless of the rotated position of the nozzle manifold 84. To one side of the sleeve 82, a pair of nozzles 88 and 89 are mounted in the nozzle manifold 84 and project outwardly therefrom in opposite directions. Tothe other side of the sleeve 82, two other nozzles 90 and 91 are mounted in the nozzle manifold 84 and project outwardly in opposite directions. The nozzles 88 and 90 are parallel to one another and the nozzles 89 and 91 are parallel to one another. The nozzles 88 through 91 are identically constructed and, as shownin FIGS. 8 and 9, each nozzle has an internal passage 93 communicating with the interior of the nozzle manifold 84. The outer end 94 of the passage 93 is converging and leads to a relatively small opening 95. A plug 96 is pressed within the passage 93. The plug 96 has a plurality of small diameter passages 97 of round cross-section through it.

Each of the nozzles 89 and 91 is slidable within a sleeve 100 that extends from one side of a plate 101. Each plate 101 is pivotally mounted on a bolt 102 between a pair of nuts 103 and 104 that act as lateral guides. The bolt 102 is mounted on its center in a block 105. The block 105 extends upwardly between a pair of guide ears 106 that are on a bracket 1 07 welded to the header 81. A threaded rod 109 is threaded into the block 105 and locked in place by a nut 110. The upper end of the rod 109 is threaded into a bearing support 111 and locked in place by a nut 112. A ball bearing 113 is mounted on a stud 114 that extends at right angles from the bearing support 111 and is held in place by a pin 1 15, as shown in FIG. 3. v

The bearing .75 already mentioned as being connected to the lower end ofthe water casing 50, has an annular groove 117 that receives the ball bearing 113. The annular groove 117 has upper and lower walls 1 18 and 119 against which the ball bearing 113 rides. A metal or plastic strap 120 is fastened at its ends to the pin and extends within the groove 117 to hold the ball bearing 113 within the annular groove 117 while permitting the ball bearing 1 13 to pivot or rock.

A horizontal plate is welded to the pipe 46 above the nozzles 88 and 90. A bolt 126 is threaded through the plate 125 with a nut 127 locking the bolt 126 in place. The bolt 126 clamps a V-shaped leaf spring 128 in a position to block the nozzle outlet 95 in the nozzle 88 when the nozzle 88 is swung just past the vertical position illustrated in FIG. 8. Another bolt 129 is threaded through the plate 125 and is locked in place by a nut 130. A V-shaped leaf spring 131 is clamped by the bolt 129 in a position to block the nozzle opening 95 in the nozzle 90 when the nozzle 90 is moved just past a vertical position.

A pair of plates 132 and 133 are welded to the underside of the sleeve 82, as illustrated in FIGS. 7 and 8. A block 134 between the plates 132 and 133, to which the plates 132 and 133 are connected by bolts 135, holds the plates 132 and 133 rigidly in place. The plate 132 has a horizontal extension 136. A bolt 137 is threaded through the horizontal extension 136 and is held in place by a nut 138. The bolt 137 attaches a V- shaped leaf spring 139 in a position to block the nozzle opening 95 in the nozzle 89 when the nozzle 89 is moved just past the vertical position illustrated in FIG. 8. The plate 133 has a horizontal extension 140. A bolt 141 is threaded through the plate extension 140 and is held in place by a nut 142. The bolt 137 attaches a V- shaped leaf spring 143 in a position to block the nozzle opening 95 in the nozzle 91 when the nozzle 91 is moved just beyond the vertical position. The ends of the nozzles 88-91 have tapers 144 to facilitate depression of the adjacent leaf springs 128, 131, 139 and 143 upon return of the nozzles into contact with the leaf springs.

The drive control for the motor 24 includes a fourway reversing valve 145 having a valve housing 146 (see FIGS. and 11) mounted on a bracket 147 that is bolted to the housing 21. The valve 145 has a pair of outlet hoses 148 and 149 that alternately communicate with an inlet hose 150 according to the position of an internal slide (not shown) in a manner known to the art. A pair of pins 151 and 152 connected to opposite ends of the slide project from opposite sides of the valve housing 146. The pins 151 and 152 are in the paths of movement of two plates 153 and 154. The

plates 153 and 154 are mounted on a common rod 155 that is slidable within the housing 146 between the position illustrated in FIG. 10 and the position illustrated in FIG. 11. The position of the rod 155, and therefore of the plates 153 and 154, is controlled by the position of a toggle lever 156. The toggle lever 156 is spring-loaded by a tension spring 157 mounted between the toggle lever 156 and the housing 146. The spring 157 biases the toggle lever 156 toward either the position shown in FIG. 10 or the position shown in FIG. 11 to provide a snap action.

A pair of plates 158 and 159 for actuating the toggle lever 156 are threaded to adjustable positions on a threaded rod 160. At its upper end, the rod 160 is connected to an extension 161 of the plate 25 that slides with the motor 24. The extension 161 projects through a vertical slot 162 in the housing 21. In place of the double switch valve shown, a four-way, two-position valve, with snap action operator and no sliding or rotating seals is used as an alternate to the valve shown.

An automatic throttle valve 163 has a housing 164 that is mounted by suitable means on the side of the four-way reversing valve 145. A cable 165 that is connected between the plate extension 161 and the housing 164 is wound about a stem on the automatic throttle valve 163.

The two air outlet hoses 148 and 149 lead from the four-way reversing valve 145 to the motor 24. Air in one hose 148 causes the piston-type rotary motor 24 to be operated in one direction, whereas, air supplied through the other hose 149 causes the motor 24 to be operated in the reverse direction. The inlet hose to the four-way reversing valve 145 is connected to the outlet (not shown) of the throttle valve housing 164. Inlet air to the throttle valve is supplied by a hose 166.

The hose 166 leads from two branch tubes 167 and 168. Air is delivered to the two branch tubes 167 and 168 by another air tube 169 connected to a suitable source of compressed air (not shown). A manually adjustable needle valve 170 is connected in the branch tube 168 for setting a rate of flow through the tube 168. A normally closed cam valve 171 is connected in the tube 167. The cam valve 171 is operated by a cam follower 172 that rides on the cam surface 37 of the large cam 35, the cam follower 172 projecting through a slot 173 in the side of the housing 21.

The tank washer 20 is adapted to be mounted over a tank 175. For this purpose, a plate 176 is welded to the water casing 50 to enable the tank washer 20 to be fastened .by bolts 177 extending through the plate 176 and threaded into the flanged collar 178 that surrounds the access opening 179 of the tank 175.

OPERATION- A threaded rod 38 and a cam 35 are selected for most effective cleaning of the particular tank 175. Different rods 38 having different thread pitches are available. These different thread pitches provide selected variation of the spacing between tracks of liquid streams emitting from the nozzles 88 through 91 and of the total time required for lineal travel of the threaded rod 38 between the limits defined by the positions ofthe switch actuator plates 151 and 152. The selection of a cam 35 is to supply a desired camming surface configuration for the most effective speed variation through each rotation of the threaded rod 38, according to the tank being cleaned.

The rod 38 is replaced by simply removing the bolts 41 and 48 to disconnect the previously installed rod and removing the bolts 45 to release the split plate 43 and the fixed nut 42. The cam 35 is replaced by removing the bolts 34 and 40 to permit removal of the rod 31. Then, the motor 24 can be slid from the housing 21 and the selected cam 35 and rod 38 placed in position, followed by re-installing the various bolts.

The length of travel of the rod 38 is adjusted by adjusting the positions of the switch actuator plates 158 and 159 on the threaded rod 161. This is done by simply turning the plates 158 and 159 to the selected positions. Ordinarily, the travel of the rod 38 is adjusted to between 3 and 5 inches. Now, with the tank washer 20 installed by threading the bolts 177 through the plate 176 and into the collar 178, and with the air hose 169 connected to a suitable source of compressed air and the liquid inlet pipe 57 connected to a suitable source of liquid, the tank washer 20 is ready for operatron.

Operation begins with the threaded rod 38 in its uppermost position. This means that the pipe 46 connected to the rod 38 is in its uppermost position so the nozzle manifold 84 is in its uppermost position. This uppermost position is established as one that will pivot the plates 101 upwardly slightly because of the engagement of the collars 100 with the. nozzles 89 and 91. This slight upward pivoting of the plates 101 swings the nozzles 88 through 91 slightly past vertical positions and into engagement with the leaf springs 128, 131, 139 and 143 to positions in which these leaf springs respectively block the nozzle orifices 95 of the nozzles 88 through 91.. Thus, when the tank washer 20 is not operating and when it is first started, all the nozzles are automatically blocked even though liquid is being supplied through the liquid inlet pipe 57 and thence through the openings 80 into the pipe 46 and through one of the openings 87 in the nozzle manifold 84 to be distributed to the nozzles 88 through 91. This automatic closing of the nozzle. orifices v95 is particularly important in applications for which the tank washer is permanently installed in a tank- With the nozzle orifices 95 closed, none of the product handled by the tank 175 can flow into the nozzle orifices 95.

As air. is supplied through the air inlet tube 169, the air flows through the branch tube 168 and through the tube 166 to the four-way reversing valve 145. Since the tank washer 20 is being started with the threaded rod 38 and the other components in theiruppermost positions, the toggle 156 and the actuator plate 153 will be in the positions-shown in FIG. 11, depressing the pin 151 and actuating the valve to cause air to be supplied through the air tube 148 to the motor 24 and to block the supply of air through the air tube 149. The supply of air through the tube 148 operates the motor 24 to rotate the threaded rod 38 in a direction that drives it downwardly as it rotates within the stationary nut 42. On this initial operation of the motor 24, the automatic throttling valve 163 will be in its full open position because it is desired to rotate the threaded rod 38 at the maximum speed when the nozzles 88 through 91 are intheir generally vertical positions and to gradually reduce the rotational speed of the rod 38 as the nozzles 88-91 swing toward generally horizontal positions.

As the motor 24 operates to rotate the threaded rod 38, and the threaded rod 38 thereby moves downwardly as it threads itself through the stationary nut 42, the pipe- 46 also moves downwardly. Since the assembly of the block 105, the rod 109,'and the bearing 7 support 111 is, of fixed length, the initial downward movement of the pipe 46 causes the plates 101 to pivot counter clockwise as viewed in FIG. 3. As soon as these plates have pivoted to horizontal positions, swinging the nozzles 88-91 to vertical positions, the nozzle orifices 95 are moved clear of the leaf springs 128, 131, 139 and 143.Therefore, the liquid being supplied to the nozzles 88-91 flows through the stream straighteners 97 and out the nozzle orifices 95 against the inner wall of the tank 175. Of course, as the threaded rod 38 is rotating it rotates the pipe 46 and therefore rotates the nozzle manifold 84 to direct these initial streams of liquid sprayed from the nozzles 88-91 in very small circles.

Since the initial circles traversed by the liquid streams are very small, relatively short paths are covered in each 360 rotation cycle of the rod 38. Hence, the automatic throttle valve 163 is set to admit the maximum air to the tube 148-and operate the motor 24 at maximum speed. As the motor 24 continues to rotate the rod, the rod moves further downwardly, moving the pipe 46 further downwardly and swinging the plates 101 further in counter clockwise directions as viewed in FIG. 3. This swings the nozzles 88-91 further in counter clockwise directions as viewed in FIG. 8 as they gradually move from the vertical-positions there illustrated toward horizontal positions. As the nozzles 88 through 91 are gradually swung from the vertical positions, the circular areas of impingement of the liquid streams emitting from the nozzles 88 through 91 gradually enlarge. However, at the same time, the automatic throttle valve 163, as actuated by the winding of the cable on its stem, gradually reduces the speed'of rotation of the rod 38 as caused by the motor 24. This variation in speed thus compensates for the gradually increasing circumference of the circular areas of impingement of the liquid streams flowing from the nozzles 88 through 91.

As the motor output shaft 28 rotates, it rotates the cam 35. When the cam rotates, its cam surface 37 also rotates. As the cam surface 37rotates, the cam follower 172 is moved away from and then toward the axis of the threaded rod 38. As the cam follower 172 moves away from the axis of the rod 38, it opens the cam valve 171, permitting some of the supplied air from the tube 169 toflow through the branch tube 167. This additional air combines with the air flowing from the branch tube 168 in the tube 166 to increase the total rate of air flow to the throttle valve 163. When the cam valve 171 thus increases the rate of air flow, the speed of rotation of the motor 24 is increased. In this manner, the speed of rotation of the motor 24 can be varied in each 360 cycle of rotation. The cam valve 171 causes the rod 38 to be rotated relatively rapidly when the nozzles 88 through 91 are sweeping past those portions of the tank 175 that are relatively close to them and to be rotated relatively slowly when the nozzles 88 through 91 are sweeping past areas of the tank 175 relatively far from then, such as the more remote corners. The cam valve 171 repeats the variations of speed of the motor 24 for each rotation of its output shaft 28 as established by the configuration of the cam surface 35.

When the threaded rod 38 has been rotated until it has threaded its way through the stationary nut 42 to its lowermost position, at which time the nozzles 88 through 91 will have been moved to or beyond horizontal positions, the actuator plate 158 will have been moved downwardly with the rod 160 and the plate 25 connected to the slidably mounted motor 24. As the plate 158 moves downwardly, it moves the toggle 156 downwardly and finally to and past center. Because of the spring 157, the toggle 156 cannot stop on center, but will snap positively to the down position shown in FIG. 10. This shifts the rod 155 and the plates 153 and 154 upwardly, releasing the pin 151 and depressing the pin 152 to reverse the valve. Now, air is admitted,

through the air tube 149 to the motor 24 but air is blocked from flowing through the tube 148 to the motor. This reverses the motor 24, reversing the direction of rotation of its output shaft 28 and reversing the direction of rotation of the threaded rod 38. Now, therefore, the threaded rod 38 threads through the nut 42 and is driven upwardly, reversing all of the functions and operations previously described. As the rod 38 moves upwardly, the automatic throttling valve 163 gradually increases the speed of the motor 24, subject to the variations produced by the cam valve 171 during each rotation of the motor output shaft 28. Finally, the rod 38 again moves to its extreme upper position and the nozzles 88 through 91 are rotated to and past their vertical position until their orifices 95 are again opposite the blocking leaf springs 128, 131, 139 and 143, and the tank washer is then stopped.

FIGS. 12 through 22 illustrate a modified nozzle assembly 185 that may be substituted for the nozzle assembly 83. The nozzle assembly 185 has a header 186 comprising a vertical sleeve 187 that is fastened to the pipe 46 by a bolt 188, with a horizontal cylinder 189 formed at the lower end of the vertical connecting sleeve 187. The cylinder 189 has a plurality of vertical slots 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200 and 201 through its side that communicate with the interior 202 of the cylinder 189. The slots 190-195 are in one V-row and the slots 196-201 are in another parallel V-row. Each slot extends around approximately a 45 arc of the circumference of the cylinder 189.

This, with the motions to be described, provides complete spray coverage of every point on the interior of a tank to be cleaned.

A cylindrical manifold 204 is rotatable within the cylinder 189. (See FIGS. 17 through 21.) The manifold 204 has a hollow interior 205 and has an opening 206 through its upper side to maintain communication between the pipe 46 and the hollow interior 205 of the manifold 204.

A pair of plates 208 and 209 are mounted on the ends of the manifold 204 by bolts 210. The plates 208 and 209 are bent inwardly to provide extensions 211 and 212 respectively that are fastened by nuts 213 onto a bolt 214. The bolt 214 is pivotally supported in the block 105 that has already been described. As the pipe 46 moves vertically, the plate extensions 211 and 212 pivot on the bolt 214 to swing through approximately a 45 are between the positions illustrated in FIG. 13 and FIG. 15. The swivel mounting of the ball 113 within the annular groove or track 117 permits the block 105 to swing inwardly as necessary to accommodate the pivotal movement of the plates 208 and 209.

A plurality of nozzle units are mounted in the manifold 204. As FIG. 17 illustrates, two nozzle units 218 and 219 are mounted in the manifold in line with the slots 190 and 196 respectively. The inner ends 220 and 221 of the nozzle units 218 and 219 communicate with the interior 205 of the manifold for receiving liquid from within the manifold. The outer ends 222 and 223 (see FIG. 12) of the nozzle units 218 and 219 have liquid outlets. These nozzle units 218 and 219 are of different lengths to provide for different spray configurations. Identical nozzle units are aligned with the slots 195 and 201 respectively.

FIG. 18 shows two nozzle units 225 and 226 mounted in the manifold 204 and aligned with the slots 191 and 197 respectively. The inner ends 227 and 228 respectively receive liquid from within the manifold interior 205, and the outer ends of the nozzle units 225 and 226 have jet openings 229 and 230 for emitting streams of liquid. Identical nozzle units are aligned with the slots 194 and 200 respectively.

FIG. 19 shows two nozzle units 231 and 232 mounted in the manifold 204 and aligned with the slots 192 and 198. The inner ends 233 and 234 respectively of the nozzle units 231 and 232 receive liquid from the manifold interior 205, and the outer ends have jet outlets 235 and 236 for spraying the liquid. Identical nozzle units are aligned with the slots 193 and 199 respectively.

All of the nozzle units 218, 219, 225, 226, 231 and 232 may incorporate stream straighteners, such as the stream straightener 96 shown in FIGS. 8 and 9.

The lengths of the slots 190 through 201 and the positions of the jet outlets 222, I223, 229, 230, 235 and 236 are such that, when the plates 208 and 209 are in the horizontal positions illustrated in FIG. 13, the jet outlets are positioned at the upper ends of the slots as illustrated in FIG. 12. As the plates 208 and 209 rotate from the horizontal positions illustrated in FIG. 13 toward the positions illustrated in FIG. 15, they rotate the manifold 204 to swing the nozzle units, moving the jet outlets 222, 223, 229, 230, 235 and 236 downwardly within the slots. When the plates 208 and 209 have reached the upper limit of their are of movement, illustrated in FIG. 15, the jet outlets 222, 223, 229, 230, 235 and 236 will have moved, downwardly beyond the lower edges of the slots 190-201 and will be blocked by the cylinder 189, as illustrated in FIG. 14 and in FIGS. 20, 21 and 22. Thus, as the nozzle assembly 185 rotates and reciprocates through the approximately '45, the entire interior of a tank will be sprayed by liquid from the nozzle units 218, 219, 225, 226, 231 and 232. Yet, thenozzle assembly 185 is self closing.

FIG. 23 illustrates another form of nozzle assembly 240 which is automatically self closing whenever a liquid is being supplied to the pipe 57. The nozzle assembly 240 is intended to be a substitute for each of the nozzles 88, 89, and 91. Each nozzle assembly 240 comprises a cylinder 241 that would be mounted in the manifold 84 in the positions shown for the nozzle cylinders 88, 89, 90 and 91 in FIGS. 7 and 8. The cylinder 241 has a bottom wall 242 into which a valve housing 243 is threaded. The valve housing 243 has a closed upper end 244, a cylindrical side wall 245, and a lower end 246 having a jet opening 247 through it. There are inlet openings 248 through the cylindrical side wall 245 just above the lower end 242 of the cylinder 241.

A valve member 249 is mounted within the valve housing 243 and extends below a piston 250. The piston is above the liquid inlet openings 248 and is biased downwardly by a compression spring 251. An 0- ring seal 252 is mounted in the side of the piston 250. If desired, an unstressed coil spring 254 may be mounted in the space between the valve member 249 and the cylindrical side wall 245 of the valve housing 243, to impart a helical flow path to the liquid.

The lower end 255 of the valve member 249 tapers to a needle 256 that projects through the jet outlet 247 when the valve member is closed. The valve member will always be closed when no liquid is being supplied, and, therefore, the valve assembly 240 will remain closed. When liquid is supplied. through the pipe 57 and the pipe 46 to the manifold 84, the liquid flows through the cylinder 241 of each valve assembly 240 and thence through the openings 248. The pressure of the liquid bears against the lower side of the piston 250 to move the piston upwardly against the force of the compression spring 251. The force of the compression spring sure., When the piston 250 rises, the'needle 256 withdraws fromthe jet openings 247, and the liquid entering the openings 248 flows on to be sprayed through to the jet opening 247. As soon as the liquid supply is stopped, the spring 251 automatically closes the nozzle assembly 240.

What is claimed isi l. A tank washer comprising a housing, a pipe slidably supported by the housing, a nozzle assembly connected to the pipe, means to connect the tank washer to a tank to be cleaned with the nozzle assembly and at least part of the pipe projecting within the tank, means to reciprocate the pipe relative to the housing, means to rotate the pipe relative to the housing, thereby reciprocating the nozzle assembly and rotating the nozzle assembly", the nozzle assembly comprising at least one nozzle having a nozzle outlet orifice and responsive to variations in the cam surface, and means liquid passages communicating the outlet orifice with i the interior of the pipe, means for mounting the nozzle for rotation about an axis perpendicular to the axis of the pipe, means to cause-rotation of the nozzle .about said perpendicular axis in response to lineal movement of the'pipe,-and meansto supply liquid to the interior of the pipe and to transmit the liquid through the nozzle liquid passages to the nozzleoutlet orifice, whereby the pipeactsboth tosupply liquid and transmit reciprocating and rotating motion to the nozzle, the rotating motion being about two-axes.

'- 2. The tankwasher of claim 1 including means to vary the lineal speed of reciprocation of the pipe and therefore of the nozzle assembly.

3. The tank-washer of claim 1 including means to vary the speedof rotation of the pipe and'therefore of the nozzle assembly-during each 360 cycle of rotation.

4. Thetank washer of claim 1 wherein the means to just the supply of air to the air motor to vary the rate of rotation ofthe motor output shaft in response to the lineal position of the threaded rod, and means to vary the supply of air to the air motor in a predetermined program throughout each 360 cycle of rotation of the motor output shaft.

7. The tank washer of claim 5 including a four-way reversing valve having a spring-loaded actuating element for reversing the supply of air to the air motor to reverse operation of the air motor.

8. The tank washer of claim 4 including means to interchange threaded rods for selecting the pitch of the threads thereon.

' 9. The tank washer of claim 5 wherein the means to vary the supply of ,air' to the air motor in each 360 cycle of rotation of the threaded rod comprises a cam having a cam surface, a cam valve in the air supply line to mount the cam for replacement by other cams havmount the fixed nut for replacement by other fixed nuts, and means to prevent rotation of the fixed nut in its mounting.

11. The tank washer of claim 1 wherein the nozzle assembly has a plurality of nozzles.

12. The tank washer of claim 11 wherein each nozzle comprises a tubular passage leading to a converging wall surrounding the nozzle outlet orifice, and a stream straightener disk positioned within the tubular passage adjacent the converging wall, the stream straightener disk having a plurality of passages through it parallel to the direction of flow of, liquid through the nozzle, each of the plurality of passages being of round cross-section.

13. The tank washer of claim 1 wherein the means to cause rotation of the nozzle in response to lineal movement of. the pipe comprises a linkage of fixed length connected between the nozzle and the housing, .the

nozzle having a pivotal connection to the linkage, a track and follower connection between the housing and the linkage to permit the linkage to revolve around the housing as the pipe is rotated, and means to hold the follower in contact with the track.

14. The tank washer'of claim 1 including means for automatically closing the nozzle in response to rotation of the nozzle to a predeterminedposition upon lineal movement of the pipe.

15. The tank washer of claim 14 wherein the automatic closing means comprises spring-biased stops supported by the housing and positioned to block the nozzle outlet orifice upon rotation of the nozzle to the aforesaid predetermined position.

16. The tank washer of claim 1 wherein there are a plurality of nozzles having nozzlev outlets, a cylindrical manifold for supporting the nozzles, a cylinder, a plurality of slots in the cylinder the nozzles being aligned with the slots in the cylinder, the manifold being rotatable in response to lineal movement of the pipe to move the nozzle orifices relative to the slots for spraying liquid through the slots.

17. The tank washer -of claim 16 wherein the manifold is rotatable to a position at which the nozzles are moved beyond the slots. and are blocked from spraying liquid by the cylinder.

18. The tank washer of claim 1 wherein the nozzle comprises a valve housing having an outlet orifice, a valve member movable toward and away from the outlet orifice, a piston connected to the valve, a spring to bias the piston in a direction to move the valve member into a position blocking the outlet orifice, a liquid inlet to the valve housing, the liquid inlet communicating with the interior of the pipe, a face on the piston exposed to liquid in the liquid inlet and positioned to respond to liquid pressure to move the valve member away from the outlet orifice, the total liquid force on the said piston face being greater than the spring force. 

1. A tank washer comprising a housing, a pipe slidably supported by the housing, a nozzle assembly connected to the pipe, means to connect the tank washer to a tank to be cleaned with the nozzle assembly and at least part of the pipe projecting within the tank, means to reciprocate the pipe relative to the housing, means to rotate the pipe relative to the housing, thereby reciprocating the nozzle assembly and rotating the nozzle assembly, the nozzle assembly comprising at least one nozzle having a nozzle outlet orifice and liquid passages communicating the outlet orifice with the interior of the pipe, means for mountinG the nozzle for rotation about an axis perpendicular to the axis of the pipe, means to cause rotation of the nozzle about said perpendicular axis in response to lineal movement of the pipe, and means to supply liquid to the interior of the pipe and to transmit the liquid through the nozzle liquid passages to the nozzle outlet orifice, whereby the pipe acts both to supply liquid and transmit reciprocating and rotating motion to the nozzle, the rotating motion being about two axes.
 2. The tank washer of claim 1 including means to vary the lineal speed of reciprocation of the pipe and therefore of the nozzle assembly.
 3. The tank washer of claim 1 including means to vary the speed of rotation of the pipe and therefore of the nozzle assembly during each 360* cycle of rotation.
 4. The tank washer of claim 1 wherein the means to reciprocate the pipe and to rotate the pipe comprises a reversible rotary motor, a threaded rod connected to the output shaft of the motor, a fixed nut mounted within the housing, the threaded rod being threaded through the fixed nut so that, as the rod is rotated by the motor, it is driven lineally as it threads through the fixed nut.
 5. The tank washer of claim 4 wherein the motor is a piston-operated air motor having a rotary output shaft.
 6. The tank washer of claim 5 including means to adjust the supply of air to the air motor to vary the rate of rotation of the motor output shaft in response to the lineal position of the threaded rod, and means to vary the supply of air to the air motor in a predetermined program throughout each 360* cycle of rotation of the motor output shaft.
 7. The tank washer of claim 5 including a four-way reversing valve having a spring-loaded actuating element for reversing the supply of air to the air motor to reverse operation of the air motor.
 8. The tank washer of claim 4 including means to interchange threaded rods for selecting the pitch of the threads thereon.
 9. The tank washer of claim 5 wherein the means to vary the supply of air to the air motor in each 360* cycle of rotation of the threaded rod comprises a cam having a cam surface, a cam valve in the air supply line responsive to variations in the cam surface, and means to mount the cam for replacement by other cams having other cam surface configurations.
 10. The tank washer of claim 4 including means to mount the fixed nut for replacement by other fixed nuts, and means to prevent rotation of the fixed nut in its mounting.
 11. The tank washer of claim 1 wherein the nozzle assembly has a plurality of nozzles.
 12. The tank washer of claim 11 wherein each nozzle comprises a tubular passage leading to a converging wall surrounding the nozzle outlet orifice, and a stream straightener disk positioned within the tubular passage adjacent the converging wall, the stream straightener disk having a plurality of passages through it parallel to the direction of flow of liquid through the nozzle, each of the plurality of passages being of round cross-section.
 13. The tank washer of claim 1 wherein the means to cause rotation of the nozzle in response to lineal movement of the pipe comprises a linkage of fixed length connected between the nozzle and the housing, the nozzle having a pivotal connection to the linkage, a track and follower connection between the housing and the linkage to permit the linkage to revolve around the housing as the pipe is rotated, and means to hold the follower in contact with the track.
 14. The tank washer of claim 1 including means for automatically closing the nozzle in response to rotation of the nozzle to a predetermined position upon lineal movement of the pipe.
 15. The tank washer of claim 14 wherein the automatic closing means comprises spring-biased stops supported by the housing and positioned to block the nozzle outlet orifice upon rotation of the nozzle to the aforesaid predetermined position.
 16. The tank washer of claim 1 wherein there are a plurality of nozzles havinG nozzle outlets, a cylindrical manifold for supporting the nozzles, a cylinder, a plurality of slots in the cylinder the nozzles being aligned with the slots in the cylinder, the manifold being rotatable in response to lineal movement of the pipe to move the nozzle orifices relative to the slots for spraying liquid through the slots.
 17. The tank washer of claim 16 wherein the manifold is rotatable to a position at which the nozzles are moved beyond the slots and are blocked from spraying liquid by the cylinder.
 18. The tank washer of claim 1 wherein the nozzle comprises a valve housing having an outlet orifice, a valve member movable toward and away from the outlet orifice, a piston connected to the valve, a spring to bias the piston in a direction to move the valve member into a position blocking the outlet orifice, a liquid inlet to the valve housing, the liquid inlet communicating with the interior of the pipe, a face on the piston exposed to liquid in the liquid inlet and positioned to respond to liquid pressure to move the valve member away from the outlet orifice, the total liquid force on the said piston face being greater than the spring force. 